Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

A way of figuring out when it's the best time to plant alstromeria is to examine the USDA zone info for Northfield.

Planting Calendar for Alstromeria

Frost tolerance for alstromeria:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Alstromeria do well in moderate cold which tells us that you can plant them a little bit earlier than other frost tender plants.

The earliest that you can plant alstromeria in Northfield is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant alstromeria and expect a good harvest is probably August. Any later than that and your alstromeria may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your alstromeria indoors.

Last Frost Date

The average date of last frost is May 15 in Northfield. It might get as low as -25°F during the coldest months of winter.

It's important to remember that USDA zone info for Northfield is an average and the actual date of last frost is different every year. Half of the time in Northfield you get a frost after May 15 so make sure that you are ready to cover your alstromeria if you have one of those late frosts.

USDA Zone Info for Northfield

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Northfield

You may be interested in your other planting guides for Northfield.